Air flow elevator



Aug. 16, 1955 L. K. MAULSBY AIR FLOW ELEVATOR 2 Sheets-Sheet 1 Filed Jan. 2, 1955 INVENTOR.

BY M, M

A TTORNEY Aug. 16, 1955 L. K. MAULSBY AIR FLOW ELEVATOR 2 Sheets-Sheet 2 Filed Jan. 2, 1953 [eon A. Mau/sby 1N VEN TOR.

A TTOR/VE Y United States Patent @fifiee 2,715,461 Patented Aug. 16, 1955 AIR FLOW ELEVATOR Leon K. Maulsby, San Antonio, Tex.

Application January 2, 1953, Serial No. 329,419

7 Claims. (Cl. 209-139) This invention relates to an air flow elevator adapted to lift small particled material, as Seeds including beans, barley, cracked nuts and the like, and to separate therefrom particles of greater bulk and different weight such as dross and dirt including chaff, hulls, broken fragments, partly consumed or worm-eaten seed meats and other type of matter foreign to the material to be cleaned. It is an object of this invention to provied an air flow elevator which is adapted to carry harvested material upwardly in an air blast to an expansion chamber wherein lighter particles continue in an upward path and heavier particles drop by gravity from the reduced pressure stream.

It is also an object of this invention to provide an air flow elevator having a hood on the top portion thereof constituting the separating chamber and which has a vented extension of a reduced cross-section opposite the discharge thereinto to dampen or choke the velocity of the feed into such hood.

It is a further object of this invention to provide an air fiow elevator having an adjustable deflector vane in the separating chamber and immediately beyond the delivery end of the riser to enable a variable setting and division of the air stream according to the relative sizes and weights of different types of stock to be processed so that the lighter waste portions are diverted upwardly and the heavy, good seed moves toward the velocity dampening portion of the hood to fall by gravity.

It is a further object of this invention to provide an air fiow elevator of this type which has an outlet in the reduced cross-section portion of the hood to permit the outward escape of air through a screen over the outlet opening, such outlet serving as an adjustor to regulate the back pressure built up as a result of the air entering the reduced cross-section portion.

It is also an object of this invention to provide an air flow elevator of this class having a hood with a screened outlet to permit the escape of air and waste matter therefrom while screening the product particles discharged into the hood from passing out through such screen, screens of various mesh being employed for various size materials to be deflected.

It is yet another object of this invention to provide an air flow elevator of particles from a bin into said elevator, as well as means to adjust the amount of air flow which is diverted to abet the discharge of particles from such bin.

It is also another object of this invention to provide an air flow elevator of this class which is provided with a vertically downwardly extending spout at the base of its upward discharge riser, so that heavier, bulkier, and extraneous objects may fall from the air stream within the riser and be separated from the particles moving upwardly.

It is yet a further object of this invention to provide an access door in the elevator duct adjacent the bin through which stones, nails and other heavy objects which drop to the floor of the duct may be manually removed.

Other and further objects will be apparent when the specification is considered in connection with the drawings in which:

Fig. 1 is an elevator, part in section, to show the gen eral configuration and the details of the elevator construction adjacent the bin.

Fig. 2 is a plan view taken along line 2-2 of Fig. 1.

Fig. 3 is a sectional elevation of the hood.

Figv 4 is a sectional view taken along line 44 of Fig. 3.

Fig. 5 is a fragmentary sectional elevation taken along line 55 of Fig. 3.

As shown in Fig. l, the elevator 1 has a frame 2 in which is mounted a blower 3 which receives air thereinto and discharges it outwardly through the substantially horizontally extending duct portion 4. This duct portion has a plate 5 extending at a slight angle to the longitudinal axis of the duct 4 and spaced below the top 6 of such duct. This arrangement thus provides a by-pass passage 8 to divert a portion of the discharged air more materially into contact with the particles to be discharged through the outlet 9 of the feed hopper or bin 10.

To regulate the area of contact between such by-pass and the bin outlet, the slide plate 11 is provided, having a slot therein, not shown, but extending longitudinally of such plate, so that the wing screw 12 may be threaded into the side 13 of the bin and thus threadably adjusted to bear upon the slide plate in various portions to regulate the area of contact 15 between the air discharged through the passage 8 and the particles passing downwardly from the bin and through the outlet 9.

A similar slide plate 16 is provided, having a slot, not shown, through which the Wing screw 17 extends to thread into the side 13 of the bin so that the wing screw may be threaded to hear at 19 under the slide plate 16 in various positions to thereby regulate the discharge area of the outlet 9 at the bottom of the bin.

It can thus be seen that the volume of particles discharged from the bin may be regulated and, also the velocity may be regulated by the contact area 15. This velocity of the air flowing through the by-pass 8 may be so adjusted that, within limits, a fine control is provided for the particles discharged into the upwardly curved portion or elbow 26 of the duct 4.

It often happens that field crop to be cleaned includes stones or other foreign objects too heavy to be lifted by the air discharged from the elevator, and these will fall from the bin and collect on the bottom of the duct 4, and therefore the slide plate door 21 is provided to slide with the guides 22 on the outer side of the duct portion 20 to uncover the side opening 23 so that such large particles or objects may be periodically and manually removed from the duct.

Above the duct portion 2% a substantially vertically extending riser portion 24 is provided to terminate upwardly in the outwardly curved discharge portion or elbow 25 to which the one end of the chambered hood 26 is connected at 27.

The hood 26 consists of an expansion chamber having an upwardly extending portion 28 and a portion 29 extending downwardly at an angle diverging in relation to the portion 28 from such connection and terminating in a down-spout 3% having the gravity outlet 31 through which may drop the heavy seed or grain separated from the reduced pressure stream carrying the lighter weight chaff and waste upwardly. Outwardly of the spread apart upper portion 28 and down-spout 30, and opposite to and axially aligned with the riser discharge or outlet 32 at the connection 27, there is provided a reduced cross-sectional area portion 33, which converges to an arcuate end wall 34.

A slide plate 37 is provided to slide in guides 38 on 3 either side of the hood portion 33, such slide plate sliding over the opening 36 which is covered with the mesh 35. Thus the size of the air exit opening 36 can be regulated according to the size and weight of the seed to be separated and to move the same toward the outlet 31 by discharge of air from the hood at a rate which controls the degree of back pressure and prevents building up of back pressures within the hood 26 in excess of that required for gravity separation of the particular material being operated upon. As shown in Fig. 4, this opening 36 is provided on one side of the hood only, but optionally, this invention considers that an opposed opening 36, of the same type of construction, can be provided on the opposite slidable within a recess, not shown, Within the retainer 41 and below the slot 44.

The wing nut 45 is threadable on the outer end of such screw and when tightened to bear upon the outer surface of the lever 43 will adjustably lock the lever in position to thereby position the damper to suit the type of field crop and relative weights and volumes of good seed and refuse.

In order to prevent larger particles leaving the portion 28, while passing the smaller trash and dust therethrough, the screen 46 is provided to be insertable through the slot 47 at the connection 48 between the hood and the reverse ben'd discharge duct 49. As shown in Fig. 5, slots 56 are provided in which may slide the side frame members 51 of the screen 46, whereas the side frame member 52 of such screen may rest, when the screen is fully inserted, on the ledge 53 provided at the connection 48. It can thus be seen that by providing the screen 46 of varied meshes, it is possible to control the size range between the waste particles desired to be passed through the screen 46 and the product particles desired cross-section portion, in volume in excess of that vented through the opening 26 will create a back pressure region to cushion the following air as it is discharged into the hood, and dampens and reduces its velocity of discharge for a gentle handling of the good material and avoidance V of violent impact and injury thereto.

It can thus be seen that an elevator can be provided which can adjustably control the volume of material, as seed, which may be fed from the hopper to prevent piling up in the way duct, and also the velocity of its discharge into such duct, and also an elevator may be provided which is adapted to adjustably dampen the velocity of inertia discharge of material to prevent the bruising thereof, prior to the final delivery of the material, as by gravity into a receiving means. It is therefore stated that this invention broadly includes such an elevator, in accordance with the description hereinabove set forth in this paragraph.

What is claimed is:

1. In an elevator employing air as the transporting medium, the combination of, a blower having an air intake and a discharge, a duct connected to said discharge and projected upwardly, a laterally projecting hood connected to the upper end of said duct and having an upwardly directed outlet and a downwardly directed outlet, said hood beyond said outlets converging opposite said 4 connection to form a back pressure controlling extension having a pressure relief vent therein and a feed bin from which material is discharged into said duct.

2. In an elevator employing air as the transporting medium, the combination of, a blower having an air intake and a discharge, a duct connected to said discharge and extending upwardly therefrom, a hood connected to the upper end of ,said duct and forming a separating chamber having an upwardly directed outlet, a downwardly directed outlet, and a back pressure extension beyond said outlets to act as a resilient cushion against impact of heavier separated particles, and an adjustable vent in said extension for the regulation of back pressure build-up.

3. In an elevator employing air as the transporting medium, the combination of, a blower having an air intake and a discharge, a duct connected to said discharge and extending substantially horizontally and then curved to extend substantially vertically upward, a hood connccted to the upper end of said duct and converging opposite said connection to form an outer end chamber of reduced cross-sectional area, an opening in said hood between said connection and said end chamber through which materials separated in said hood may drop downwardly, a bin over said substantially horizontally extending duct portion and adapted to discharge thereinto material to be elevated, said horizontally extending duct portion having a longitudinally extending plate extending thereacross between said blower and said bin to bypass air to said bin discharge, and an adjustable by-pass valve to control the volume of air by-passed to said bin discharge.

4. In an elevator employing air as the transporting medium, the combination of, a blower having an air intake and a discharge, a duct connected to said discharge, a delivery riser forming part of'said duct, a separating hood connected to the upper end of said riser duct and converging opposite said connection to form an outer end chamber of reduced cross-sectional area, an opening in said hood between said connection and said end chamber through which materials supplied to said hood may drop downwardly, a bin to discharge material to be elevated into said duct below the riser and a down- 1 spout extending from the base of the riser and in axial T alignment therewith and through which objects which heavier materials may drop downwardly, a bin to dis-' charge material to be elevated in the duct, said hood having an upper opening therein above said duct outlet end for the upward flow of lighter materials and an adjustable bathe in the hood inthe path of duct delivery to divide the same with said extension and said drop opening on one side thereof and said upper opening on the other side thereof.

6. An air delivery separator of the character described, including an air blower conveyor to move material for separation according to particle weight, ,a riser duct constituting a part of the conveyor, an enlarged separating chamber extending laterally of the delivery end of said riser and receiving discharge therefrom, said chamber having an upwardly directed outlet above the riser delivery end and 'a downwardly directed outlet in its lower portion, a chamber extension beyond the downwardly directed outlet and in axial alignment with the air blast from said delivery end of the riser, and a H controlled air vent in said extension for regulating back pressure air pocketed in said extension and therefor the rate of progress of separated material to said downwardly directed outlet.

7. In a separator of the character described, an air stream delivery duct for material to be separated into relative weight groups, an enlarged chamber into which said duct discharges the material entrained air stream, said chamber having an expansion space and a reduced dimension back pressure pocket beyond the expansion space in axial alignment with the duct discharge to check inertia velocity of heavier material particles, a downwardly directed outlet from said space for gravity discharge of the heavier particles, an outlet in the upper part of the space for air flow carrying the lighter particles a deflector bafiie within the space operable in the path of the duct discharged stream to direct a portion of the stream to the upper outlet, and means to adjust bafiie position to vary stream division.

References Cited in the file of this patent UNITED STATES PATENTS 

